Posaconazole: an oral triazole with an extended spectrum of activity

Posaconazole nanocrystals dry powder inhalers for the local treatment of invasive pulmonary aspergillosis

Invasive pulmonary aspergillosis poses a significant threat to immunocompromised patients, characterized by high mortality rates. Posaconazole (PSZ), a second-generation triazole antifungal, exhibits broad-spectrum activity but suffers from limited pulmonary concentrations and notable systemic side effects when administered orally or intravenously. This study focuses on optimizing PSZ nanocrystals-agglomerated particles for dry powder inhalers (DPIs) to enhance solubility, dissolution rates, and pulmonary deposition, ultimately improving therapeutic efficacy while minimizing systemic adverse effects. We employed wet medium milling and spray-drying techniques to formulate PSZ nanocrystals-agglomerated DPIs. Various stabilizers including HPMC, HPC, Soluplus, and PVPK30, were systematically evaluated to optimize physicochemical properties. Aerosolization performance was assessed using the Next Generation Impactor, while antifungal efficacy was evaluated through in vitro and in vivo studies. The optimized PSZ DPIs demonstrated significant enhancements in solubility and dissolution rates, with a fine particle fraction (FPF) of 78.58 ± 3.21%, ensuring optimal lung delivery. In vitro experiments revealed potent effects with minimal cytotoxicity to lung cells. In vivo studies indicated that the optimized formulation achieved a Cmax/AUC0→∞ ratio in lung tissues that was 27.32 and 6.76-fold higher than that of the oral suspension, highlighting increased local drug concentrations. This approach presents a scalable, cost-effective strategy for the pulmonary delivery of PSZ, ensuring high drug loading and promising clinical outcomes in treating pulmonary fungal infections.

Thiophene-Linked 1,2,4-Triazoles: Synthesis, Structural Insights and Antimicrobial and Chemotherapeutic Profiles

The reaction of thiophene-2-carbohydrazide 1 or 5-bromothiophene-2-carbohydrazide 2 with various haloaryl isothiocyanates and subsequent cyclization by heating in aqueous sodium hydroxide yielded the corresponding 4-haloaryl-5-(thiophen-2-yl or 5-bromothiophen-2-yl)-2,4-dihydro-3H-1,2,4-triazole-3-thione 5a-e. The triazole derivatives 5a and 5b were reacted with different secondary amines and formaldehyde solution to yield the corresponding 2-aminomethyl-4-haloaryl-2,4-dihydro-3H-1,2,4-triazole-3-thiones 6a-e, 7a-e, 8, 9, 10a and 10b in good yields. The in vitro antimicrobial activity of compounds 5a-e, 6a-e, 7a-d, 8, 9, 10a and 10b was evaluated against a panel of standard pathogenic bacterial and fungal strains. Compounds 5a, 5b, 5e, 5f, 6a-e, 7a-d, 8, 9, 10a and 10b showed marked activity, particularly against the tested Gram-positive bacteria and the Gram-negative bacteria Escherichia coli, and all the tested compounds were almost inactive against all the tested fungal strains. In addition, compounds 5e, 6a-e, 7a-d and 10a exhibited potent anti-proliferative activity, particularly against HepG-2 and MCF-7 cancer cell lines (IC50 < 25 μM). A detailed structural insight study based on the single crystals of compounds 5a, 5b, 6a, 6d and 10a is also reported. Molecular docking studies of the highly active antibacterial compounds 5e, 6b, 6d, 7a and 7d showed a high affinity for DNA gyrase. Meanwhile, the potent anti-proliferative activity of compounds 6d, 6e and 7d may be attributed to their high affinity for cyclin-dependent kinase 2 (CDK2).

Novel 1, 2, 4-Triazoles as Antifungal Agents

The development of innovative antifungal agents is essential. Some fungicidal agents are no longer effective due to resistance development, various side effects, and high toxicity. Therefore, the synthesis and development of some new antifungal agents are necessary. 1,2,4-Triazole is one of the most essential pharmacophore systems between five-membered heterocycles. The structure-activity relationship (SAR) of this nitrogen-containing heterocyclic compound showed potential antifungal activity. The 1,2,4-triazole core is present as the nucleus in a variety of antifungal drug categories. The most potent and broad activity of triazoles have confirmed them as pharmacologically significant moieties. The goal of this review is to highlight recent developments in the synthesis and SAR study of 1,2,4-triazole as a potential fungicidal compound. In this study, we provide the results of a biological activity evaluation using various structures and figures. Literature investigation showed that 1, 2, 4-triazole derivatives reveal the extensive span of antifungal activity. This review will assist researchers in the development of new potential antifungal drug candidates with high effectiveness and selectivity.

Dental and Oral Manifestations of COVID-19 Related Mucormycosis: Diagnoses, Management Strategies and Outcomes

It has been nearly two years since the pandemic caused by the novel coronavirus disease (COVID-19) has affected the world. Several innovations and discoveries related to COVID-19 are surfacing every day and new problems associated with the COVID-19 virus are also coming to light. A similar situation is with the emergence of deep invasive fungal infections associated with severe acute respiratory syndrome 2 (SARS-CoV-2). Recent literature reported the cases of pulmonary and rhino-cerebral fungal infections appearing in patients previously infected by COVID-19. Histopathological analysis of these cases has shown that most of such infections are diagnosed as mucormycosis or aspergillosis. Rhino-orbital-cerebral mucormycosis usually affects the maxillary sinus with involvement of maxillary teeth, orbits, and ethmoidal sinuses. Diabetes mellitus is an independent risk factor for both COVID-19 as well as mucormycosis. At this point, there is scanty data on the subject and most of the published literature comprises of either case reports or case series with no long-term data available. The aim of this review paper is to present the characteristics of COVID-19 related mucormycosis and associated clinical features, outcome, diagnostic and management strategies. A prompt diagnosis and aggressive treatment planning can surely benefit these patients.

Design, synthesis, biological screening and molecular docking studies of novel multifunctional 1,4-di (aryl/heteroaryl) substituted piperazine derivatives as potential antitubercular and antimicrobial agents

In this paper, two series of novel multifunctional 1, 4-di (aryl/heteroaryl) substituted piperazine derivatives (6a-d & 7a-d) were synthesized, characterized, and evaluated for their antitubercular, antibacterial, and antifungal activities. A step-wise reduction, bromination and substitution reactions on various aldehydes resulted in alcohols (2a-d), bromides (3a-d), and titled novel compounds (6a-d & 7a-d) in moderate to good yields (48-85%). The novel compounds were evaluated for their antitubercular and antimicrobial activities. Compound 7a exhibited promising antitubercular activity (MIC: 0.65 µg/mL) almost equal to the Rifampicin, while the rest of the compounds were moderately active against MTB H37Rv except 6b. Compounds 7a and 6b showed good activity against tested fungal pathogens. Compounds 7a and 7b were proven as the best bacterial agents. Molecular docking studies were in agreement with the in-vitro results. Docking analyses show that all the synthesized molecules bind to the target protein Mtb RNAP (PDB ID: 5UHC) fairly strongly. All the compounds were evaluated for their in vitro cytotoxicity effect using the MTT assay method against human cancer cell line MCF-7. The compounds demonstrated growth inhibitory effect on the cell line with significant IC₅₀ values ranging between 8.20 and 34.45 µM. Most importantly, compound 7a displayed good binding affinity towards the tested protein with binding energy -7.30 kcal/mol and a stronger hydrogen bond distance of 2.2 Å with ASN-493 residue. Thus, the present research highlighted the potential role of novel piperazine derivatives as potential antitubercular, and antimicrobial candidates and further good research into optimization might result in the development of new antitubercular drug candidates.

Pharmacokinetics and Pharmacodynamics of Posaconazole

Posaconazole is typically used for preventing invasive yeast and mold infections such as invasive aspergillosis in high-risk immunocompromised patients. The oral suspension was the first released formulation and many pharmacokinetic and pharmacodynamic studies of this formulation have been published. Erratic absorption profiles associated with this formulation were widely reported. Posaconazole exposure was found to be significantly influenced by food and many gastrointestinal conditions, including pH and motility. As a result, low posaconazole plasma concentrations were obtained in large groups of patients. These issues of erratic absorption urged the development of the subsequently marketed delayed-release tablet, which proved to be associated with higher and more stable exposure profiles. Shortly thereafter, an intravenous formulation was released for patients who are not able to take oral formulations. Both new formulations require a loading dose on day 1 to achieve high posaconazole concentrations more quickly, which was not possible with the oral suspension. So far, there appears to be no evidence of increased toxicity correlated to the higher posaconazole exposure achieved with the regimen for these formulations. The higher systemic availability of posaconazole for the delayed-release tablet and intravenous formulation have resulted in these two formulations being preferable for both prophylaxis and treatment of invasive fungal disease. This review aimed to integrate the current knowledge on posaconazole pharmacokinetics, pharmacodynamics, major toxicity, existing resistance, clinical experience in special populations, and new therapeutic strategies in order to get a clear understanding of the clinical use of this drug.

Retrospective analysis of goal drug level attainment of posaconazole for invasive fungal infection prophylaxis in patients with acute myeloid leukemia pre- and post-switch to tablet formulation

Background

Posaconazole is approved for invasive fungal infection prophylaxis in patients with hematologic malignancies. Posaconazole suspension is plagued by poor oral absorption and dietary requirements that are difficult for patients to meet. The delayed-release tablet formulation of posaconazole may be taken without regards to meals and has significantly better oral absorption than posaconazole suspension.

Objectives

We sought to determine if a switch to posaconazole tablets improved steady-state drug level attainment for invasive fungal infection prophylaxis in patients with acute myeloid leukemia.

Methods

All adult inpatients with acute myeloid leukemia undergoing chemotherapy, who received posaconazole for invasive fungal infection prophylaxis between 2012 and 2015, were included. The primary outcome was proportion of patients with first posaconazole level greater than 700 ng/mL. Secondary outcomes included proportion of patients with first posaconazole level greater than 1000 ng/mL, invasive fungal infection within 100 days, and adverse drug events.

Results

Forty patients received posaconazole tablets and 34 patients received suspension. Posaconazole levels were significantly higher at first measurement in patients receiving tablet than suspension (1296 ng/mL vs. 788 ng/mL, p < 0.01). Thirty-seven patients receiving tablets had a serum drug level greater than 700 ng/mL on first measurement versus 18 receiving suspension (p < 0.01). Patients receiving tablets were also more likely to have a serum drug level over 1000 ng/mL on first measurement (26 vs. 11, p < 0.01). Rates of invasive fungal infection and adverse events were not statistically different.

Conclusions

Patients receiving posaconazole tablets attained significantly higher serum drug levels than those receiving suspension.

NLLSS: Predicting Synergistic Drug Combinations Based on Semi-supervised Learning

Fungal infection has become one of the leading causes of hospital-acquired infections with high mortality rates. Furthermore, drug resistance is common for fungus-causing diseases. Synergistic drug combinations could provide an effective strategy to overcome drug resistance. Meanwhile, synergistic drug combinations can increase treatment efficacy and decrease drug dosage to avoid toxicity. Therefore, computational prediction of synergistic drug combinations for fungus-causing diseases becomes attractive. In this study, we proposed similar nature of drug combinations: principal drugs which obtain synergistic effect with similar adjuvant drugs are often similar and vice versa. Furthermore, we developed a novel algorithm termed Network-based Laplacian regularized Least Square Synergistic drug combination prediction (NLLSS) to predict potential synergistic drug combinations by integrating different kinds of information such as known synergistic drug combinations, drug-target interactions, and drug chemical structures. We applied NLLSS to predict antifungal synergistic drug combinations and showed that it achieved excellent performance both in terms of cross validation and independent prediction. Finally, we performed biological experiments for fungal pathogen Candida albicans to confirm 7 out of 13 predicted antifungal synergistic drug combinations. NLLSS provides an efficient strategy to identify potential synergistic antifungal combinations.

Drug combinations represent a promising strategy for overcoming fungal drug resistance and treating complex diseases. There is an urgent need to establish powerful computational methods for systematic prediction of synergistic drug combination on a large scale. Based on the assumption that principal drugs which obtain synergistic effect with similar adjuvant drugs are often similar and vice versa, NLLSS was developed to predict potential synergistic drug combinations by integrating known synergistic drug combinations, unlabeled drug combinations, drug-target interactions, and drug chemical structures. NLLSS has obtained the reliable performance in the cross validation and experimental validations, which indicated that NLLSS has an excellent performance of identifying potential synergistic drug combinations. Out of 13 predicted antifungal synergistic drug combinations, 7 candidates were experimentally confirmed. It is anticipated that NLLSS would be an important and useful resource by providing a new strategy to identify potential synergistic antifungal combinations, explore new indications of existing drugs, and provide useful insights into the underlying molecular mechanisms of synergistic drug combinations.

Diagnosis and initial management of musculoskeletal coccidioidomycosis in children

BACKGROUND

Coccidioidomycosis is an invasive fungal infection caused by the inhalation of aerosolized spores of Coccidioides spp., which reside in the arid soil of the southwestern United States and northern Mexico. Approximately two thirds of cases are asymptomatic, and the remainder usually present with mild flu-like symptoms. Dissemination of coccidioidomycosis is rare, and can lead to extrapulmonic diseases including meningitis, osteomyelitis, and skin and soft-tissue involvement. The purpose of this study is to report our experience with musculoskeletal coccidioidomycosis in children.

METHODS

This was a retrospective chart review of patients with musculoskeletal infection with Coccidioides spp. at a tertiary care pediatric hospital from 1997 to 2010, identified by a search of ICD-9 codes and hospital diagnoses. Demographic and clinical data were collected from medical records, including the age of the patient, sex, white blood cell count, immunocompetence, length of stay, location of involvement, and initial treatment. In total, 20 children were identified with musculoskeletal coccidioidomycosis. The mean age was 12.3 years (range, 2 to 17 y) at time of diagnosis. Diagnostic criteria included positive imaging tests (plain film+MRI), serologic positive titers, and/or biopsy with positive cultures.

RESULTS

The most common presenting symptom was bone pain (100%); only 3 (15%) patients had accompanying signs/symptoms of pulmonary infection. Only 2 (5%) patients had a white blood cell count >15×10/L (5%). Locations of infection included the foot (28%), knee (14%), spine (12%), forearm (10%), lower leg (6%), and other sites (30%). Fluconazole was the most common antifungal agent used (75%). Surgical intervention was required in 10 (50%) patients.

CONCLUSIONS

This is the first series that has described musculoskeletal coccidioidomycosis exclusively in children. This study suggests that the initial presentation of this disease can be nonspecific and difficult to recognize in children. Clinicians should consider this diagnosis when faced with a musculoskeletal infection in children from the southwestern United States and northern Mexico.

LEVEL OF EVIDENCE

IV (case series).

Fatal Breakthrough Mucormycosis in an Acute Myelogenous Leukemia Patient while on Posaconazole Prophylaxis

Posaconazole is a new oral triazole with broad-spectrum antifungal activity. Posaconazole has also shown a significant advantage of preventing invasive fungal infection compared to fluconazole or itraconazole in patients with prolonged neutropenia. Indeed, posaconazole has been commonly used for antifungal prophylaxis in patients undergoing remission induction chemotherapy for acute myelogenous leukemia or myelodysplastic syndrome. We experienced a case of fatal mucormycosis despite posaconazole prophylaxis. To our knowledge, this is the first reported case of fatal breakthrough mucormycosis in a patient receiving posaconazole prophylaxis during remission induction chemotherapy in Korea. This case demonstrated that breakthrough fungal infection can occurs in patients receiving posaconazole prophylaxis because of its limited activity against some mucorales.

Safety and pharmacokinetics of isavuconazole as antifungal prophylaxis in acute myeloid leukemia patients with neutropenia: results of a phase 2, dose escalation study

Isavuconazole is a novel broad-spectrum triazole antifungal agent. This open-label dose escalation study assessed the safety and pharmacokinetics of intravenous isavuconazole prophylaxis in patients with acute myeloid leukemia who had undergone chemotherapy and had preexisting/expected neutropenia. Twenty-four patients were enrolled, and 20 patients completed the study. The patients in the low-dose cohort (n = 11) received isavuconazole loading doses on day 1 (400/200/200 mg, 6 h apart) and day 2 (200/200 mg, 12 h apart), followed by once-daily maintenance dosing (200 mg) on days 3 to 28. The loading and maintenance doses were doubled in the high-dose cohort (n = 12). The mean ± standard deviation plasma isavuconazole areas under the concentration-time curves for the dosing period on day 7 were 60.1 ± 22.3 μg · h/ml and 113.1 ± 19.6 μg · h/ml for the patients in the low-dose and high-dose cohorts, respectively. The adverse events in five patients in the low-dose cohort and in eight patients in the high-dose cohort were considered to be drug related. Most were mild to moderate in severity, and the most common adverse events were headache and rash (n = 3 each). One patient in the high-dose cohort experienced a serious adverse event (unrelated to isavuconazole treatment), and two patients each in the low-dose and high-dose cohorts discontinued the study due to adverse events. Of the 20 patients who completed the study, 18 were classified as a treatment success. In summary, the results of this analysis support the safety and tolerability of isavuconazole administered at 200 mg and 400 mg once-daily as prophylaxis in immunosuppressed patients at high risk of fungal infections. (This study is registered at ClinicalTrials.gov under registration number NCT00413439.).

Infectious complications of stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) is an accepted treatment for a variety of hematologic malignancies. The profound immunosuppression these patients experience adversely affects their risk of infection. This risk is much higher than in the general population and requires aggressive diagnostic and therapeutic interventions. The chapter will outline the major infections after HSCT.

Posaconazole treatment in Korea: single-center experience over 5 years

PURPOSE

Posaconazole is a second-generation triazole with a broad spectrum. However, there is a lack of data to support a significant role for posaconazole in the treatment of invasive fungal infection (IFI), especially in Korea. Until recently, posaconazole was available only through the Korean Orphan Drug Center. This study was designed to review the use of posaconazole at a single-center in Korea.

MATERIALS AND METHODS

Data from patients who received posaconazole treatment at Catholic Blood and Marrow Transplantation Center were retrospectively reviewed between January 2007 and September 2012.

RESULTS

A total of 11 cases (3 males and 8 females, median age 52 years) received posaconazole. Five patients were given the drug for mucormycosis, two for invasive aspergillosis, and four for unspecified IFI for which galactomannan (GM) assays were negative. The treatment duration ranged from 4-250 days. Three patients received posaconazole for management refractory IFI, two for intolerance of previous antifungal therapy, and six for long-term maintenance treatment. The overall successful response rate to posaconazole was 55% (six of eleven patients). Five of eleven patients died during the study period. However, only one death was attributed to the progression of IFI. None of the patients discontinued posaconazole therapy due to adverse events.

CONCLUSION

Posaconazole is an attractive oral antifungal agent for salvage treatment of IFI, particularly upon diagnosis of mucormycosis or in cases in which mucormycosis cannot be ruled out due to a negative GM.

Antimicrobial prophylaxis and outpatient management of fever and neutropenia in adults treated for malignancy: American Society of Clinical Oncology clinical practice guideline

PURPOSE

To provide guidelines on antimicrobial prophylaxis for adult neutropenic oncology outpatients and on selection and treatment as outpatients of those with fever and neutropenia.

METHODS

A literature search identified relevant studies published in English. Primary outcomes included: development of fever and/or infections in afebrile neutropenic outpatients and recovery without complications and overall mortality in febrile neutropenic outpatients. Secondary outcomes included: in afebrile neutropenic outpatients, infection-related mortality; in outpatients with fever and neutropenia, defervescence without regimen change, time to defervescence, infectious complications, and recurrent fever; and in both groups, hospital admissions, duration, and adverse effects of antimicrobials. An Expert Panel developed guidelines based on extracted data and informal consensus.

RESULTS

Forty-seven articles from 43 studies met selection criteria.

RECOMMENDATIONS

Antibacterial and antifungal prophylaxis are only recommended for patients expected to have < 100 neutrophils/μL for > 7 days, unless other factors increase risks for complications or mortality to similar levels. Inpatient treatment is standard to manage febrile neutropenic episodes, although carefully selected patients may be managed as outpatients after systematic assessment beginning with a validated risk index (eg, Multinational Association for Supportive Care in Cancer [MASCC] score or Talcott's rules). Patients with MASCC scores ≥ 21 or in Talcott group 4, and without other risk factors, can be managed safely as outpatients. Febrile neutropenic patients should receive initial doses of empirical antibacterial therapy within an hour of triage and should either be monitored for at least 4 hours to determine suitability for outpatient management or be admitted to the hospital. An oral fluoroquinolone plus amoxicillin/clavulanate (or plus clindamycin if penicillin allergic) is recommended as empiric therapy, unless fluoroquinolone prophylaxis was used before fever developed.

Current concepts in antifungal pharmacology

The introduction of new antifungal agents (eg, echinocandins, second-generation triazoles) in the past decade has transformed the management of invasive mycoses to the point that drug toxicity is no longer the major limiting factor in treatment. Yet, many of these newer antifungal agents have important limitations in their spectrum of activity, pharmacokinetics, and unique predisposition for pharmacokinetic drug-drug interactions and unusual toxicities associated with long-term use. This article reviews key pharmacological aspects of systemic antifungal agents as well as evolving strategies, such as pharmacokinetic-pharmacodynamic optimization and therapeutic drug monitoring, to improve the safety and efficacy of systemic antifungal therapy.

Therapeutic drug monitoring of posaconazole in hematology adults under posaconazole prophylaxis: influence of food intake

Posaconazole (PCZ) is given at 200 mg three times daily as a fungal prophylaxis in neutropenic hematologic malignancy patients. A relationship between exposure, plasma concentration, and efficacy is suggested. The objectives of this prospective study were to analyze the PCZ plasma concentration in hematology adults at high risk of developing invasive fungal infections (IFIs), and factors that could have an impact on the PCZ plasma concentration. PCZ plasma concentrations were measured after 2, 7, 10, 14, and 21 days of PCZ prophylaxis. Factors such as gender, age, body weight, posology, treatment duration, mucositis, proton pump inhibitor (PPI) use, and food intake were studied. Sixty-three patients were included, with a median age of 52 years (range 17-70) and a median weight of 75 kg (range 47-150). The median PCZ plasma concentration of the 63 patients ranged from 0.42 to 0.48 mg/L. At day 2, 30% of PCZ plasma concentration were under 0.35 mg/L, and at day 7, 74% were <0.70 mg/L. PCZ plasma concentrations were not affected by gender, age, body weight, or treatment duration. We found that food intake had a high influence on PCZ plasma concentrations (p = 0.0049). PCZ was well tolerated. One patient has developed a probable IFI, probably related to a low exposure to PCZ. PCZ therapeutic drug monitoring (TDM) is essential in order to early detect patients with low concentrations, to assess the etiology of such results, and to decide on the treatment strategy to apply.

Disseminated fusariosis occurring in two patients despite posaconazole prophylaxis

Posaconazole is widely used for prophylaxis against invasive fungal infections in patients undergoing myeloablative therapy. Disseminated fusariosis is a serious invasive mold infection in such patients. Preclinical and clinical studies indicate activity of posaconazole against Fusarium. We describe two cases of disseminated fusariosis that occurred despite posaconazole prophylaxis.

Interactions between antifungal and antiretroviral agents

IMPORTANCE OF THE FIELD

Since the advent of combination antiretroviral therapy, the incidence of opportunistic infections has declined and the life expectancy of HIV-infected people has significantly increased. However, opportunistic infections, including fungal diseases, remain a leading cause of hospitalizations and mortality in HIV-infected people. With the availability of several new antiretroviral and antifungal agents, drug-drug interactions emerge as a potential safety concern.

AREAS COVERED IN THIS REVIEW

Relevant literature was identified using a Medline search of articles published up to March 2010 and a review of conference abstracts. Search terms included HIV, antifungal agents and drug interactions. Original papers and relevant citations were considered for this review.

WHAT THE READER WILL GAIN

Readers will gain an understanding of the pharmacokinetic properties of antiretroviral and antifungal agents, and insight into significant drug-drug interactions which may require dosage adjustments or a change in therapy.

TAKE HOME MESSAGE

Azole antifungal drugs, with the exception of fluconazole, pose the greatest risk of two-way interactions with antiretroviral drugs through CYP450 enzymes effects. Limited studies suggest the risk of interactions between antiretroviral drugs and echinocandins is much lower. The combination of tenofovir and amphotericin B should be used with caution and close monitoring of renal function is required.

Antifungal treatment of small animal veterinary patients

Antifungal therapy has progressed significantly with the development of new drugs directed at various processes in fungal cell metabolism. Within veterinary medicine, treatment options for systemic mycoses remain limited to amphotericin B, ketoconazole, fluconazole, and itraconazole. However, newer triazoles, echinocandins, and lipid-based formulations of amphotericin B are now approved for use in humans. This article provides a comprehensive review of the antifungal medications available for veterinary patients, and includes a brief discussion of the newer, presently cost-prohibitive, antifungal therapies used for systemic mycoses in humans.

Opportunistic fungi: a view to the future

Opportunistic fungi are a constantly evolving group of pathogens that plague a growing group of vulnerable patients. These include hospitalized patients, especially those in the intensive care unit; stem cell and solid organ transplant recipients; patients treated with immunosuppressant medications; those with advanced human immunodeficiency virus or other acquired immunodeficiency conditions; and patients with organ failure syndromes. Rapid diagnosis of invasive fungal infection is essential to optimize outcomes. Several newer nonculture-based diagnostics, including the Aspergillus galactomannan enzyme-linked immunosorbent assay, the beta-d-glucan assay and the multiplex polymerase chain reaction-based assays, may emerge as important tools facilitating early intervention with effective antifungal therapy. Newer azoles, including posaconazole, isavuconazole and ravuconazole, will potentially provide more effective therapeutic options in the future, diminishing the role for amphotericin B.

Pharmacological significance of triazole scaffold

The triazole nucleus is one of the most important and well known heterocycles which is a common and integral feature of a variety of natural products and medicinal agents. Triazole nucleus is present as a core structural component in an array of drug categories such as antimicrobial, anti-inflammatory, analgesic, antiepileptic, antiviral, antineoplastic, antihypertensive, antimalarial, local anaesthetic, antianxiety, antidepressant, antihistaminic, antioxidant, antitubercular, anti-Parkinson's, antidiabetic, antiobesity and immunomodulatory agents, etc. The broad and potent activity of triazole and their derivatives has established them as pharmacologically significant scaffolds. The basic heterocyclic rings present in the various medicinal agents are 1,2,3-triazole and 1,2,4-triazole. A large volume of research has been carried out on triazole and their derivatives, which has proved the pharmacological importance of this heterocyclic nucleus. The present paper is an attempt to review the pharmacological activities reported for triazole derivatives in the current literature with an update of recent research findings on this nuclei.

Treatment strategies for oropharyngeal candidiasis

BACKGROUND

Oropharyngeal candidiasis (OPC) is a common oral disease that may cause oral symptoms, lead to regional infection (e.g., esophageal candidiasis) and increase the risk of systemic fungal infection in the compromised host.

OBJECTIVE

Critical review of the literature of prevention and therapy.

METHODS

The literature was reviewed using PubMed, and specific keywords from the MeSH Database were used.

RESULTS/CONCLUSION

Management of OPC requires that the underlying risk factors of infection be diagnosed and managed whenever possible. Antimicrobials may be provided as topical or systemic therapy. Topical therapies may provide effective management for candidiasis in the non-compromised host and increase the control of colonization in the compromised host. Advances in prevention and management include new agents and improved mechanisms of topical drug delivery.

Itraconazole treatment of nonmeningeal coccidioidomycosis in children: two case reports and review of the literature

Coccidioides immitis causes a wide range of disease in humans. Fluconazole and itraconazole are effective treatments. Clinical evidence suggests that itraconazole is equivalent or superior to fluconazole in treating osteoarticular infections in rates of cure and recurrence. We report 2 cases of coccidioidomycosis involving bone in children successfully treated with itraconazole oral solution. Itraconazole oral solution is effective in treating nonmeningeal coccidioidomycosis in children, particularly skeletal disease, and infections that are refractory to fluconazole.

Coccidioidal meningitis: update on epidemiology, clinical features, diagnosis, and management

Coccidioidomycosis is a fungal infection endemic to geographically restricted areas of the southwestern United States, and its incidence is increasing within endemic areas. Coccidioidal meningitis, an infrequent but very severe form of coccidioidomycosis, is associated with significant mortality and morbidity. The diagnosis depends on the demonstration of coccidioidal antibody or positive culture, histopathology, or cytology in the presence of typical abnormalities of the cerebrospinal fluid. Central nervous system complications of this infection may include hydrocephalus, vasculitis, infarctions, or parenchymal abscesses. Many patients with coccidioidal meningitis can achieve remission of infection following treatment with triazole antifungal agents. However, first-line therapy with high-dose oral fluconazole is associated with a high incidence of relapse after drug discontinuation. This article summarizes the pathogenesis, epidemiology, clinical manifestations, diagnostic studies, and treatment of coccidioidal meningitis, and highlights new information regarding this devastating infection.

Fatal rhizopus pneumonia in allogeneic stem cell transplant patients despite posaconazole prophylaxis: two cases and review of the literature

Posaconazole is a triazole with broad spectrum of activity against multiple fungi including members of the fungal order Mucorales. This activity has been shown both in clinical and in vitro studies, which are critically reviewed here. It has become very popular in prophylaxis in acute myelogenous leukemia (AML) induction and in the graft-versus-host disease (GVHD) settings after 2 recent prospective trials that showed advantage of posaconazole prophylaxis compared to fluconazole or itraconazole. In this report, 2 patients are presented, in whom, despite posaconazole prophylaxis, invasive and ultimately fatal Rhizopus pulmonary infections developed. These cases are similar to a previously reported case of Rhizopus infection in a stem cell transplant recipient who also received posaconazole, indicating a potential newly recognized pattern of breakthrough infections in patients receiving posaconazole prophylaxis.